MCM Marshall Studios large ashtray w/design, signed deals Martz.

Product Name: MCM Marshall Studios large ashtray w/design, signed deals Martz.
The ashtray is large; it features six slots. It's a brown glaze on top that has almost a white ish color mixed in. It has flecking of dark white spots. The white color can be in some of the design shapes; see pics. There is an incised design of circular shapes with vertical cuts that shows underlying pottery. Good condition with no deals chips/cracks. In the interior, the glaze on part of one of the circular areas is weak; looks worn off. I think it was made that way and not damaged. Underside has a beige like rough like texture that's dull but soiled due to age/use. Original Marshall Studios sticker on underside with serial or stock number. It has a 150/0 magic marker stain on label. Nearby it has an incised signature 'Martz" M301? Light surface wear inside, nice large size and design. Measures 9.5" X 2.5".